Enhancement of static antiferromagnetic correlations by magnetic field in a superconductor La2-xSrxCuO4 with x=0.12

Elastic neutron-scattering experiments have been performed to study effects of high magnetic field on static antiferromagnetic correlations coexisting with the superconductivity in La1.88Sr0.12CuO4 (T-c=12 K) Under the field applied perpendicular to the CuO2 plane its superconductivity is severely suppressed at 10 T. The intensity of incommensurate elastic magnetic peaks around the (pi, pi) point is, on the other hand, significantly increased at 10 T by as much as 50% of that of 0 T.